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71.
Yi‐Chin Chen Sheng‐Cih Huang Dr. Yu‐Kuo Wang Dr. Yuan‐Ting Liu Prof. Dr. Tung‐Kung Wu Prof. Dr. Teng‐Ming Chen 《化学:亚洲杂志》2013,8(11):2652-2659
In this study, surface‐functionalized, branched polyethylenimine (BPEI)‐modified YVO4:Bi3+,Eu3+ nanocrystals (NCs) were successfully synthesized by a simple, rapid, solvent‐free hydrothermal method. The BPEI‐coated YVO4:Bi3+,Eu3+ NCs with high crystallinity show broad‐band excitation in the λ=250 to 400 nm near‐ultraviolet (NUV) region and exhibit a sharp‐line emission band centered at λ=619 nm under excitation at λ=350 nm. The surface amino groups contributed by the capping agent, BPEI, not only improve the dispersibility and water/buffer stability of the BPEI‐coated YVO4:Bi3+,Eu3+ NCs, but also provide a capability for specifically targeted biomolecule conjugation. Folic acid (FA) and epidermal growth factor (EGF) were further attached to the BPEI‐coated YVO4:Bi3+,Eu3+ NCs and exhibited effective positioning of fluorescent NCs toward the targeted folate receptor overexpressed in HeLa cells or EGFR overexpressed in A431 cells with low cytotoxicity. These results demonstrate that the ligand‐functionalized, BPEI‐coated YVO4:Bi3+, Eu3+ NCs show great potential as a new‐generation biological luminescent bioprobe for bioimaging applications. Moreover, the unique luminescence properties of BPEI‐coated YVO4:Bi3+,Eu3+ NCs show potential to combine with a UVA photosensitizing drug to produce both detective and therapeutic effects for human skin cancer therapy. 相似文献
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A new norlabdane diterpenoid, named vitrifolin A, was isolated from the fruits of Vitex trifolia Linn. var. simplicifolia Cham. Its structure was elucidated by mean of spectroscopic methods, including HRESIMS, IR, 1D and 2D NMR. The inhibitory effect of vitrifolin A on nitric oxide production in lipopolysaccarideactivated mouse macrophages was also evaluated. 相似文献
74.
Qiaoxia Guo Wennian Wang Weiling Teng Liwei Chen Yanqing Wang Baojian Shen 《合成通讯》2013,43(17):2574-2584
A convenient one-pot method for the synthesis of substituted quinolines via the reaction of aniline and aldehyde in the presence of a Lewis acid (AlCl3) and an oxidant (H2O2) has been developed. Hydrogen peroxide was found to promote the reaction by its function as a hydrogen hunter, hindering the formation of by-product N-alkylaniline. The effect of the oxidant on the yield and selectivity was studied. When the molar ratio of aniline, n-butyraldehyde, and H2O2 was 1:3:0.5 at 25 °C, the yield of 3-ethyl-2-propylquinoline was improved from 64% (reaction without H2O2) to 84% (with H2O2), and the quinoline selectivity was improved to almost 100%. Moreover, the reaction time was obviously reduced. The substituent effect was also investigated in this work. 相似文献
75.
A concise asymmetric total synthesis of (+)-monocerin has been accomplished. The cis-fused furobenzopyranone of monocerin was efficiently constructed via a Lewis acid-mediated stereoselective cyclization of 1,2,4-triols intermediate. 相似文献
76.
Hongni Teng Ning Li Xixi Zhu Yong Chen 《Journal of Dispersion Science and Technology》2013,34(6):828-833
Aqueous two-phase systems (ATPS) are formed in mixtures of sodium dodecylsulfate (SDS), cetyltrimethyl ammonium bromide (CTAB), and sodium bromide (NaBr). Two different kinds of ATPS appear when CTAB and SDS surfactants are in excess, respectively. Such ATPS may provide a new, useful partitioning system for separation of bovine serum albumin (BSA). The partitioning of BSA was studied in these systems. The results show that the partitioning is affected by the electrical property, the hydrophobicity and the structure of liquid crystal (LC), which exists in the top phase of the ATPS. BSA is extracted into the top phase with higher distribution coefficient when LC and BSA are oppositely charged. The hydrophobicity of LC, which can be improved by increasing the length of alkyl group, enhances the distribution coefficient. The hydrophobicity of lamellar LC and hexagonal LC is stronger than that of cubic LC, which causes extractive capability of the former is higher than the latter. 相似文献
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78.
Study of Cl−(H2O)n (n = 1–4) using basin‐hopping method coupled with density functional theory 下载免费PDF全文
Shuai Jiang Yi‐Rong Liu Teng Huang Hui Wen Kang‐Ming Xu Wei‐Xiong Zhao Wei‐Jun Zhang Wei Huang 《Journal of computational chemistry》2014,35(2):159-165
Cl?(H2O)n (n = 1–4) clusters were investigated using a basin‐hopping (BH) algorithm coupled with density functional theory (DFT). Structures, energetics, thermodynamics, vertical detachment energies, and vibrational frequencies were obtained from high‐level ab initio calculations. Through comparisons with previous theoretical and experimental data, it was demonstrated that the combination of the BH method and DFT could accurately predict the global and local minima of Cl?(H2O)n (n = 1–4). Additionally, to optimize larger Cl?(H2O)n (n > 4) clusters, several popular density functionals as well as DF‐LMP2 (Schütz et al., J. Chem. Phys. 2004, 121, 737) (second‐order Møller‐Plesset perturbation theory using local and density fitting approximations) were tested with appropriate basis sets through comparisons with MP2 optimized results. DF‐LMP2 will be used in future studies because its overall performance in describing the relative binding energies and the geometrical parameters of Cl?(H2O)n (n = 1–4) was outstanding in this study. © 2013 Wiley Periodicals, Inc. 相似文献
79.
80.
M. Q. Mehmood Hong Liu Kun Huang Shengtao Mei Aaron Danner Boris Luk'yanchuk Shuang Zhang Jinghua Teng Stefan A. Maier Cheng‐Wei Qiu 《Laser \u0026amp; Photonics Reviews》2015,9(6):674-681
This work presents analytical, numerical and experimental demonstrations of light diffracted through a logarithmic spiral (LS) nanoslit, which forms a type of switchable and focus‐tunable structure. Owing to a strong dependence on the incident photon spin, the proposed LS‐nanoslit converges incoming light of opposite handedness (to that of the LS‐nanoslit) into a confined subwavelength spot, while it shapes light with similar chirality into a donut‐like intensity profile. Benefitting from the varying width of the LS‐nanoslit, different incident wavelengths interfere constructively at different positions, i.e., the focal length shifts from 7.5 μm (at λ = 632.8 nm) to 10 μm (at λ = 488 nm), which opens up new opportunities for tuning and spatially separating broadband light at the micrometer scale.